The present invention concerns a connector coupled by pressure for telecommunications systems. More specifically, the invention concerns a connector to be employed to couple, in a quick and electrically perfect way, a coaxial cable with a female coaxial connector, that may be provided with an outer thread and a central contact, for example, in an elastic central contact for F type connectors.
It is known to connect coaxial cables with electrical or electronic circuits. More particularly, it is known for coaxial connections to be employed to realize systems for the distribution of radio and TV signals. Metallic clamps are generally employed. Such clamps are inexpensive but have different technical drawbacks.
These drawbacks are even more evident when considering advancements in the state of the art making it common to use signal reception and distribution systems having frequencies higher than 2000 MHz, such as in satellite reception systems, cable networks, MMDS systems and so on.
In order to obviate these drawbacks, it is advisable to use male and female coaxial connectors. The first is coupled to the coaxial cable and the other to the final circuit. The techniques already known generally provide for the connection of coaxial cables with coaxial connectors, the welding or screwing of the two poles to the cable of the connector ends, or the screwing or crimping of the male coaxial connector onto the screen conductor of the coaxial cable. Further, the coupling of a cable to a connector is done by screwing or coupling, or by the introduction of two metallic parts, a rigid one and an elastic one, respectively.
On the basis of these solutions, past and present systems, patented or not, and commercial coaxial connectors have been developed. The choice of these kinds of solutions for the coupling of coaxial cables is due to the limited use of coaxial joints employed on professional apparatuses only, and are highly expensive relative to the cost of one or two traditional coaxial joints.
The most recent technological development has broadened the application of coaxial cables, and consequently, the application of relevant connectors which, if employed for applications such as radio frequencies distribution in the domestic buildings, also influence the cost of the work necessary to obtain a technically efficient but cheap and easy to apply coupling.
Within this field of application, it includes the solution suggested according to the present invention, which is the ability to satisfy the above needs, by means that are completely different from systems already employed.
The main object of the present invention is to obtain a connector that allows a coupling between a coaxial cable and a female coaxial connector so as to allow, within a range of frequencies between 0 and up to or beyond 2000 MHz, a constant impedance power transfer, with a maximum concentration, a maximum electromagnetic screening, a minimum loss of signal, a minimum mismatching and a minimum parasitic capacitance.
A further object of the invention is to obtain a connector that allows a connection between a coaxial cable and a female coaxial connector that has a good mechanical coupling but is also easily removable.
A further object of the invention is to obtain a connector that allows a connection between a coaxial cable and a female coaxial connector that is easily made, and can be made without the need of any specific tool, with a minimum number of sizes and that is also very inexpensive.
These and other objectives are obtained according to the present invention utilizing a connector coupled by pressure for telecommunication systems that employs as the central pin of the connection, the rigid central conductor of the coaxial cable. The connection is fixed by pressure on the outer surface of the female connector by a sleeve slidable on the cable. The sleeve has, on its rear portion, a diameter corresponding to or slightly greater than the diameter of the coaxial cable. The sleeve has on its front portion a diameter slightly greater than the one of the outer surface of the female connector.
It is therefore a specific object of the invention to produce a coaxial connector, particularly for the mechanical and electrical connection of the outer screening conductor of a coaxial cable with the outer screening of a female coaxial connector. The coaxial connector comprises a slidable sleeve having a first and a second coaxial inner cylindrical seat. The first seat has an inner diameter corresponding to, or slightly greater than the outer diameter of the cable. The second seat has an inner diameter slightly greater than the outer diameter of the outer wall of the connector. The sleeve allows for a pressure coupling of the coaxial cable screen between the sleeve coaxial connector and the outer wall of the female coaxial connector.
Preferably, according to the invention, at least one projection can be provided within the second seat. Also according to the invention, the portion of the connector corresponding to the first seat can be long in order to obtain a greater coupling stability alternatively, this portion can be short to reduce the dimensions. Furthermore, according to the invention, outside the second seat, close to the outer connection zone with the first seat, a circular projection can be provided. Also, according to the invention, the connection zone between the first and second seats can be realized by a sloped wall. Also, according to the invention, spaced longitudinal ribs can be provided outside said second seat. Also, according to the invention, on the inner surface of the first and second seat a roughness can be provided.
Within the first seat, longitudinal lugs can be further provided, preferably three lugs circumferentially spaced at 120xc2x0. Also, within said second seat, longitudinal lugs can be provided, preferably three lugs circumferentially spaced at 120xc2x0.
Always according to the invention, the connector is used for the connection of the coaxial cable screen made up of metallic braid, with the threaded outer screening of a female coaxial connector. Or it is used for the connection of the coaxial cable screen made up of one or more metallic foils, with the threaded outer screening of a female coaxial cable, or for the connection of a coaxial cable screen, made up of metallic, braid and one or more metallic foils, with the outer screening of a female coaxial connector.
Furthermore, according to the invention, the coaxial connector can be made up of plastic material, elastic material, such as rubber, or elastic metallic material.